Lathe spindle speed control



w. G. HOELSCHER LATHE SPINDLE SPEED CONTROL 5 Sheets-Sheet l Filed Nov.-23, 1940 INVENTOR.

MATTONEYfi w. G. HOELSCHER 2,332,381-

LATHE SPINDLE SPEED CONTROL Filed Nov; 25, 1940 Oct. 19, 1943.

5 Sheets-Sheet 2 a a :g

*3 l i m g1 1N VENTOR.

ATTORNEw 19, 19430 w. G. HOELSCHER 2,332,331

LATHE SPINDLE SPEED CONTROL I Filed Nov. 23, 1940 5 Sheets-Sheet 3 INVENTOR.

@q BY M44 4? W WMATTQRNEYJ Oct. 19, 1943. w HOELSCHER 2,332,381

LATHE SPINDLE SPEED CONTRO L Filed Nov. 25, 1940 5 Sheets-Sheet 4 BY flu. Q MIMMZATTORNEYJ Oct. 19, 1943. w. G. HOELSCHER LATHE SPINDLE SPEED CONTROL 5 Sheets- Sheet 5 Filed Nov. 23, 1940' INVENTOR.

Patented Qct. 19, 1943 LATHE SP'INDLE SPEED CONTROL William G. Hoelscher, Cincinnati, Ohio, assignor to The American Tool Works Company, Cincinnati, Ohio, a corporation of Ohio Application November 23, 1940, Serial No, 366,893

6 Claims. (01. 74-3375) This invention relates to machine tools and is particularly directed to improvements in the headstock of a lathe. More particularly,.the imv provements are concerned with the transmission contained within the headstock for driving the lathe spindle.

It has been the object of the present inventor to provide an improved speed change transmission including an eflicient, simplified arrangement of gearing extending fromthe driving pulley to the spindle, in which the gear arrangement may be easily modified to be capable of providing different ranges of speeds, for example, nine, eighteen, or twenty-seven speeds. The arrangement of shafts and gearing is such that 'the builder or manufacturer of the lathe may produce a standard headstock and may alter this headstock to change the range alforded thereby,

merely by altering the gear set-up adjacent the power input end of the transmission; that is, ad jacent the clutch and driving pulley.

It has been a further object of the present inventor to provide animproved gear-shifting arrangement wherein a range control lever is provided for shifting to any one dfa plurality of speed ranges and a speed change lever is provided for changing to speeds within the ranges. These levrs are associated with an indicator plate at the front of ,thelathe in such manner that the speed changes can be read directly and with absolute ease.

It has been a further object of. this inventor to provide a lever and cam means for gear shiftin by means of a lever having a compound motion; that is, movable either vertically or horizontally. The lever is effective in the respective directions for actuating a cam in each instance for producing the appropriate gear changes. The

' shifting-levers are arranged and supported within the headstock casing so as to make it possible to move the gears with very little manual efiort. Other objects and certain advantages of this invention will be more fully apparent from the 5n line 44, Figure 3, detailing a ortion of the shifting mechanism.

Figure 51s a sectional view taken on line 5-5,

Figure 3, further illustrating the gear-shifting mechanism.

Figure 6 is a sectional view taken on line 5-4, Figure 3, illustrating the shifting lever assembly and the means extended therefrom for shiftin the gears.

Figure 7 is an enlarged detailed view of the speed indicator plate, appearing ,in Figure 1.

Figures 8 to- 11 inclusive are layout views illustrating the several shifting cams.

Figure 12 is a fragmentary sectional view taken from Figure 2 showing the sub-assembly of gears for procuring twenty-seven speeds.

Figure 13 is a view taken similar to Figure 12' replacing them with the appropriate gears, the

speed capacity of the transmission is varied. These changes are made adjacent the clutch and on what may be referred to as the power supply shaft and a short, easily removable countershaft.

The gears are shifted mechanically by means of cams and levers compactly arranged and mounted within the casing. Control of these shifting medium is accomplished by means of a lever assembly at the front of the headstock. One

of the levers shifts the gears into high, low, and

intermediate ranges, and the other lever varies the speeds within the respectiveranges. The plate provides a series of colored panels, and by virtue of the color arrangement and the position of the manipulating ends of the levers; the operator is able to ascertain immediately the speed to which the mechanism has been set. One of the levers has acompound movement; that is to say, a movement which will permit the lever to be moved either vertically or horizontally for moving the same into position registering with any.

one of horizontally and vertically arranged panels indicating the speeds within the, various ranges.

Described inv more detail, the transmission comprises a headstock casing 20 in which a spindle 2! is mounted. A face plate 22 may be used as shown in Figure 1. A cover 24 is provided to permit access to the mechanism, particularly the gear shifting mechanism which is suspended from brackets 25-26 mounted on a flange 2'I projected inwardly from the upper portion of the headstock, casing. A clutch 28 (Figure 2) controls the supply of power for the power upply shaft 29. This clutch is contained within a clutch casing 30 fixed to the end of the headstock casing. A dust cover 3| covers the clutch and drive assembly as well as m certain other mechanism associated with the headstock. A pulley 32 driven by V-type belts is journalled in ball bearing 33 in the clutch casing. It is not believed necessary to describe the clutch and drive pulley assembly in detail since this portion of the mechanism is not a part of the present invention. v

The drive shaft 29 is journalled in bearings 34-34 in the drive pulley and an inner cross wall 35 of the headstock casing. This drive shaftdrives the lubricant pump 36 in the conventional manner. Intermediate or countershafts 31 to 40 inclusive are provided in th present arrangement, intermediate the drive shaft and the spindle 2|. That portion of the drive shaft 29 between the end wall and the cross wall 35 is splined.

"I'he twenty-seven-speed arrangement is illustrated in the main view, Figure 2. A gear cluster 4| is slidably mounted on the splined portion of the drive shaft. This cluster 4| includes three gears-42, 43, and 44 listed in the order of their sizes. A set of gears is fixed on the countershaft 31 journalled between the end wall and the cross wall 35. Gears 45, 45, and 41, component to the gears 42, 43, and 44, are included. Thus, it is 35 possible to deliver three speeds to the shaft 31.

The next countershaft 38 is mounted in ball bearings in the outer end wall of the headstock casing and in intermediate wall 48. A portion of this shaft is splined. A gear cluster 49 is slidably 40 mounted on the splined portion and includes three gears 50, 5|, and 52, listed in the order of their sizes. The set of gears included on the shaft 31 includes gears 53 and 54. In addition to the gears already mentioned, these gears 53, 54, and a previously-mentioned gear 41 are component to the gears 50, 5|, and 52. Thus, nine speeds may be delivered to the shaft 38.

From this shaft 38, the drive may proceed either directly to the spindle or by way of the countershafts 39, 40. In order to accomplish this, a gear 55 is shiftably mounted on the splined portion of the shaft 38 and meshes either with the gear 58 keyed to the shaft 39 or with the internal gear portion 51 of a gear 58, loosely mounted on a plain portion of the shaft 38 directly adjacent the wall 48. The gear 58 is helical and in mesh with helical gear 59 keyed to the spindle 2|. The spindle 2| is mounted in the end walls and intermediate wall 48 of the headstock casing in roller bearings. Thus, nine speeds may be imparted to the-spindleby way of gears 58 and 59.

The shaft 39 is journalled in hearings in the interior walls 35 and 48 and the end wall of the headstock casing. A long gear 60 is formed as Part of the countershaft 39 between the interior wall 48 and the inner end wall of the headstock casing. A gear cluster 6| is in splined connection with the countershaft 40 journalled in and betweenthe interior wall 48 and the inner end wall of the headstock casing in alignment with the countershaft 38. The cluster 6| may he slid back and forth with its gear 82 in mesh with the gear 68 at all times. The gear 68 of cluster 6|,is

adapted to mesh with the gear- 84 keyed on the spindle. Gear 62 is adapted to-mesh with the gear 65 keyed to the spindle. Since the shaft 39 may be driven at nine different speeds, it is obvious that the spindle may be driven at eighteen speeds through this gear set just described. With the preceding range of nine speeds, it is then obvious that the spindle be driven at any one of twenty-seven different speeds.

The feed box gearing driven from the spindle in the usual manner is indicated generally at 89. No description of this is included since it does not constitute a part of this invention.

Shifting mechanism The range control lever 10 and the speed control lever H are mounted in the forward wall of the headstock casing. The headstock casing includes a bulge 12 upon the face of which the indicator plate 13 is mounted. The lever ll is mounted at the center of the plate and is adapted to be moved either vertically or horizontally about an axis for registering with vertically and horizontally disposed rows of insignia on the face of the indicator plate. The range control lever 10 swings horizontally to any one of three positions: namely, slow, intermediate and fast, indicated at 14 on the panel. The color, blue indicates slow: red indicates intermediate; and black indicates fast. The manipulating knob 15 of the range control lever is adapted to be disposed over and register with any one of the respective panels 14.

The lever 10 is fixed to a vertically mounted shaft 16. -This shaft is mounted in the bulge portion of the headstock casing and is disposed" across a clearance slot 11. The bulge provides a flat horizontal surface affording a bearing for the underside of the lever 10 in its swinging move- 'ments. A bifurcated arm 18 is fixed to the shaft 16 within the slot. A link 19 connects the bifurcated arm to the arm 88 of the gear segment 8| fixed on a stub shaft 82 journalledin 8. depending lug 83 of .the bracket 26. The gear segment meshes with a spur gear 84 fixed on the end of a shaft 85 (Figures 3 and 6), journalled in depending fianges of the bracket 26.

Cams 868'|- are fixed on this shaft and include the usual cam tracks configurated to shift the gear 55 and gear cluster 6| to produce the three-speed ranges. A shifting lever 88 is pivotally mounted on the bracket 26 on a vertical pivot pin 89 (Figures 3 and 6). This pivot pin is mounted in a cross member 98 of the bracket One end of the lever includes a roller 9| engaged in the cam'track of the cam 86 and the other end is connected to a shifting yoke 92 straddling the gear 62 of the gear cluster 6|. The yoke is slidably mounted on a rod 93.

One end of the hub of the yoke includes a transverse slot 94 inits upper surface. A rectangular block 95 is engaged in the slot. This block is rotatably mounted on a pin portion 98 in the end of the lever 88. Thus, swingin movement of the lever 88, as produced by the cam track, slides the yoke along the rod 93, with which it is in splined connection. This action moves the gear 62 to position of mesh with gear 55 or moves the gear 63 to position of mesh with the 0 gear 64.

The other cam 81 actuates a lever 98, also fulcrumed or mounted for swinging movement on the cross member of the bracket 25 on a pin 89. One end of this lever '98 includes a roller I08 disposed in the cam track of the cam 81. The

figurated to move the gear 55 to position of mesh either with the gear 56 or with the internal gear portion 51 of gear 58.

. Thus, the combined effect of the two canis is to produce three speed ranges. When the ear 55 is in mesh with the gear 55, the gear cluster 6| is actuated. In one position, it causes its gear 62 to mesh with gear Hand in the other, gear 63 to mesh with gear 64. These gears produce high and low speed ranges. 55 is moved into 'mesh with the internal gear portion 51 of gear 58, intermediate speed results through direct connection to the spindle.

A detent means is provided, causing the cams 86, 81 to register accurately at the three range position. As shown in Figures 3 and 6, the detent consists of a bell crank I03 pivotally mounted on the stub shaft 82.. One arm of the bell crank is connected, by means of a coil spring I04 under tension, to a pin I mounted in the When the, gear mlnal ,end lies in a circumferential groove in the rod I3l.

Referring .back to the shaft II4, which is best shown in Figures 4 and 6, it will be noted that I this shaft includes a bevel gear segment I32 fixed to its upper end and meshing with a bevel gearbracket 26. The .other arm of the bell crank is thus swung or urged upwardly at all times for ing unit I09 secured in a bore in the bulge portion of the headstock casing by means of screws H0. The coupled end of the handle or lever 1.] consists of a ball III fitted into the horizontal bore I I2 of a rotatably and translatably mounted shifting element H3. The shifter H3 is mounted in s'plined connection on the vertical shaft H4. The shaft H4 is mounted in ball bearings II 6. The lower ball bearing is contained in a boss I I5 and the upper in one end of the bracket 26. The shifter includes a rack I I! formed longitudinally and vertically thereof. This rack is in mesh with a gear II8 fastened to one end of a cam shaft H9. The shaft H9 (Figure 4) is journalled in the interior wall 48 of' the casing at one end and at the other endis journalled in a ball bearing in the outer end wall of the headstock casing.

The cam I20 is fixed to the shaft II9 toward the outer end wall of the headstock casing. This cam I20 includes a cam track configurated and arranged to actuate a lever I2I for shifting the gear cluster 49 to any one of three positions, either meshing gears 5II--53, gears 5I--54, or gears 52-41. The lever I2I is fulcrumed on a pin I 22 vertically fixed in the bracket 25. One end of the lever includes a roller I23 engaging the cam track, and the otherend carries a pivotally mounted yoke I24 straddling the gear 52 of the gear cluster 49.

A detent device is provided for registering this cam at any one of the three positions. This device includes a bell crank I25 mounted on a pin I26 supported in a lug I2I depending from the underside of the bracket 25. One end of the bell crank includes a roller I28 engageable with any one of three detent grooves I29 around the end portion of the cam. A coil spring I30, under tension between the otherend of the bell crank and a rod I3I, supported across the top of the bracket, hold the detent in operative position under tension. The spring 1 extends upwardly through an aperture in the bracket, and its ter- For this purpose, itincludes three positions.

lugs I35 depending from the bracket 26. A gear I36 is pinned to the other end of this shaft and meshes with a gear I3I formed as a part of the cam I30.

The cam I38 actuates, through itscam track, a lever I39. This lever is fulcrumed on the pin I40 and is thus-suspended from the bracket 25. The lever projects downwardly (Figure 5)' and includes a pivotally mounted blockLI4I engaged in a slot I42 in the hub of the yoke I43. This yoke is slidably mounted on a rod I44 mounted in a depending lug I45 of the bracket 25. The

yoke engages a groove I46 of the gear cluster M.

The cam track is configurated to move the gear clusterv 4| to any one of the three positions whereby any one of the sets of gears, 4245-, 4346,'or 444| are caused to mesh. A detent device, similar to the one on cam I20 is provided for registering this cam I38 in any one of its tive cams are co-related so as to. cause these shifts in the correct sequence and in accordance with the position of the lever II relative to the dial. swung laterally, the cam I38is operated, and as the lever is swung vertically, the cam I20 is operated.

Indicator plate Referring to the plate, detailed in Figure '7,

. it will be noted that a panel I49 of three speeds is provided for each position of the lever II.

The color scheme shown at I4 is utilized on each panel; that is to say, the horizontal stripes readingdrom the top down are blue, red, and black, with the appropriate speed indicated on each. When the range control lever I0 is in, let us say, slow speed, which is indicated at blue, the operator reads the blue stripe of the particular panel with which the knob of the lever II registers. Since the lever II is universally mounted in the center of the panel, it is obvious that the central or directly outward position of the lever could not be indicated on the center of the panel. This particular panel is moved down to the bottom of the panel and is indicated at I50.

Speed range varying means As illustrated in Figures 12 to 14 inclusive, and as described heretofore, it is possible to change the headstock to convert it either into a nineeighteen-, or twenty-seven-speed transmission. The changes are made on the shafts 29 and 31. The gearclust'er 4I may either contain three gears (Figure 12) or two, as shown at I5I (Figure 13) or may be a single gear 44 (Figure 14). The assembly on shaft 31 is altered to leave out the component gears omitted from the cluster. These changes can be made very readily at the outer end of the transmission by removing the clutch assembly and pulling the shafts 29 and 31. It will be noted that the shaft 31 is a short section of shafting conveniently removed and reassembled.

' The gears 42, 44 are separately removable from the gear 43 and the gears 45, 46, and 41 are separately removable. Accordingly, any one of these gears can be included or left out depending on the range of speeds desired in' the finished head- The cam tracks of the respec It will be observed that as the lever I I .is

stock. Thus, the manufacturer can stock a standard headstock casing construction and con- :ert it to either one of the three speed ranges by simply altering the gear set or assembly adjacent the clutch as described heretofore.

Having describe my invention, I claim:

1. In a lathe headstock including a spindle and a speed change gear transmission for driving the spindle, cams for shifting certain of the'gears, a shaft supporting said cams, one of said cams flxedto the shaft and the other loosely mounted thereon, a control lever mounted for universal movement, a slidably rotatably mounted shifting element, means connecting the shifting element and the lever, means connecting the shifting element and the shaft for rotating said shaft and said fixed cam directly, and means between the shifting element. and the other cam for rotating said other cam on the shaft, and shifting levers connecting the respective cams to respective gears.

2: In a lathe headstock including a spindle and speed change gear transmission for driving the spindle, cams for shifting certain of the gears, a shaft supporting said cams, one of said cams fixed to the shaft and the other loosely mounted thereon, a control lever mounted for either horizontal or vertical movement, a slidably rotatably mounted. shifting element, means connecting the shifting element and the lever, rack and gear means connecting the sthifting element and the shaft for rotating said shaft and said fixed cam directly, and rotative means between the shifting element and the other cam for rotating said other cam on the shaft.

3. ma lathe headstock including a spindle and a speed change gear transmission for driving the spindle, cams for shifting certain of the gears, a shaft supporting said cams, one of said cams fixed to the shaft and the other loosely mounted thereon, a control lever mounted for universal movement, a slidably rotatably mounted shifting element, means connecting the shifting element and the lever for either rotating or slidably moving said shifting element, one of said cams connected to said shifting element for rotation by lineal movement thereof and the other cam connected for rotation by rotative movement thereof.

4. In a lathe headstock including a spindle and a speed change gearing for driving the same; cams and levers for shifting certain of the gears, a horizontally movable lever, a vertically ,mounted shaft rotated by said lever, means coupling the shaft to certain of ,thecams forIotating the same, a second lever mounted just below the first and adapted to be moved horizontally and verti- I cally, a shifting element, said lever flexibly con-- levers extending from said cams to said gears for shifting the same, a gear on the second shaft,

a rack on the shifting element engaging the gear for rotating the shaft when the element is moved longitudinally along the splined shaft, a gear engaging the loosely mounted cam, and a connection from the splined shaft to said last-named gear for rotating the second cam when the splined shaft is rotated through the shifting element.

5. In a lathe headstock including a spindle and a speed change gearing for driving the same; cams and levers for shifting certain of the gears, a horizontally movable lever for controlling speed ranges, a vertically mounted shaft actuated by said lever, means coupling the shaft to certain of the cams for rotating the same to change speed ranges, a second lever mounted just below the first and adapted to be moved horizontally and vertically for shifting gears and effecting further speed changes within the speed ranges, an'axially and rotatively shiftable element, said second lever flexibly connected to said shiftable element, cams, respective levers extending from said cams to certain of said gears for shifting the same, and coupling means connecting said lastnamed cams for rotating one when the shiftable element is rotated and rotating the other when the shiftable element is moved axially.

6. In a lathe headstock including a spindle and a speed change gearing for driving the same; cams and levers for shifting certain of the gears, a horizontally movable lever for changing speed ranges, a vertically mounted shaft actuated by said lever, means coupling the shaft to certain of the cams for rotating the'cams to change speed ranges, a second lever mounted just below the first and having universal movement for shifting gearing and eflecting various speed changes within said speed ranges, a shiftable element actuated by said second lever, cams and levers for shifting certain others of said gears, means connecting the cams and said shiftable element, and coupling means extended from the second lever to the respective cams for operating one when the shiftable element is moved in one direction and operating the other when the shiftable element is moved in another direction.

WILLIAM G. HOELSCHER. 

